Within a matter of hours, the flies eggs begin to hatch. The larvae, we call maggots begin feeding immediately and grow quickly.

Within a just a few days (under optimum conditions) these larvae can mature and wriggle off to pupate. Within 14 days the flies hatch, almost in unison in their hundreds or even thousands.

This sudden emergence of large flies can be extremely concerning, but it needn’t be. These are nature’s cleaners and without them, the rotting body they came from would still be stinking! some of the pupae will take longer to develop than others, these flies can persist for many weeks.

Although most pupae hatch together, some of the pupae take longer to develop than others, meaning your flies can persist for many weeks.

How To Eliminate Blue Bottle & Green Bottle Flies

Because blowflies often take many weeks to hatch from their pupae, numbers will gradually increase from just a few flies appearing each day to hundreds, before finally tailing off to zero.

Fumigation is a common and efficient option when enormous numbers are present, but for smaller infestations of blow flies is pointless as the chemical used is only effective while it’s in the air, and that’s usually for no more than about an hour.

Because of this, the best option is very often, just a can of fly spray, which you can buy in the supermarket, before vacuuming up the dead bodies.

The chemical free option is to use sticky fly traps or quite simply open windows and flick the blow flies out a couple of times a day with a hand brush.